Gas burner control for domestic water heaters



Nov. '24, 1942. E. R. KOPPEL 2,303,128

I GAS BURNER CONTROL FOR DOMESTIC WATER HEATERS Filed May 6, 1940 2 Sheets-Sheet 1 Ernst RKoppeZ INVENTOR.

ATTORNEY.

Nov. 24,1942. R Kopp 2,303,128

' ens. BUfiNER-QONTRQL FOR DOMESTIC wmznnmgrsss FiI-ed May 6, 1940.. 2sheets-sheet 2 Q 1 Pateted NotnZ 23 22 f I v I 2' I Q I Gss BURNERcoN'rsoL ron DOMESTIC wuss HEATERS Application May 6, 1940, Serial No.333,814

b 3 Claims. (01.236-21) This invention relates to gas burner control forIn the drawings:

. ENT oFFlcE v domestic water heaters. Figure l is a sectional view ofthe lower end 01" In the construction of domestic water heating a tankShowin h control and thermflstfltl units, it is customary to employ acylindrical pp thereto; tank disposed with its axis vertical and havinga, F18. 2 is a horizontal section taken on line 2-2 substantialthickness of insulation around its 0! F18- 1;

sides and over the top, with a thin sheet metal at 8 is a verticalsection taken on line of casing the outside- A as burner is normallyFig. 2: 1

placed beneath the tank, inside of the casing, i 4 is a vertical sectiontaken nl ne 4-4 1" i and a chimney flue is provided upwardly through E-I V i the center of the tank. 7 Fix. 5 is a detail section showing theby-pess The gas burner has a. pilot-flame and a main for the D r. 01! lii 0 P18. 4; d

burner flame, the former operating continuously 8- 6 i8 8 fron View of h038111! s l' and the latter operating intermitt t in control-in place.

- cordanc with th demand for t, waten Here. Referring to the drawings,the water tank I has tofore, the control of the main burner flame by anouter casing 2 spaced therefrom to provide'forf means of a thermostathas entailed equipment of heat insulation A 1' cover p e 4 18 a sizerequiring its location outside of the ing, located near the bottom ofthe casing I to. provide This meant that the supply pipe for t g maccess to the burner I and to the control mecheapplied. to the mainthermostat located part way 20 e gas supply Pin i n the control up theside of the casing and that two pipes went mechanism at the bOttOm 0fthe mdown on the outside oi. the casing to the bottom The controlmechanism has i lower u 1v where they nt r d t pfloi; control and theproviding a gas chamber 8 receiving us directly burner. The unsightlyappearanc of t equipfrom the supply pipe 8.1 A circular disk valve Iment and the danger of its being tampered with normally Pressed cloud onit! mt by e by' small childr n h b recognized for some spring H in thegas chamber 8, and closes oil time and attempts have been mad t Mn thegas from the burner. when the disk valve I control thatocan be placedentirely i i t is pressed downwardlyagainst spring II it opens casing,out of sight. This, with the existing 1 and allows gas to escape fromchamber 8 past controls could only be achieved by the addition of 0 seatIt into the upper chamber l2 and through another merely ornamentalhousing around the the passage directly the heater proper.

The object of the present invention is to progg gi fi fif 'gv fifii;vide a control for the use burner which is'small supp c 85 operatedvalve l6 controlling the passase of gee a d compact and wh h l q and we.throuehportn totlle pilot burner u. 1 The main valve 0 is controlled bytwo thermo- An o i is t provide a single valve stats I. and a. Thethermostat ll extends into whichisoperatedbybothapilotthermostatandthewaterspaceinthe tankand respondstothe amsln control thermostat. 40temperature ,0! the water in the tank to open or Moth" iectistoprovide acontrolto which close the valve I. The thermostat 20 extends the assupply pipe is connected through the ebovethepilotilameandisresponsivetoits tembottom oi' the casing and in which no partexperature to provide 'the safety feature of preventtends outside of thetonin in: opening of valve I should the pilot time be- Another object toprovide my control come extinguished. Iioch thermostat preferablymechanism which is readily ldiueted and which wmpm homnmly copper u andon inner control rod 2! ol diflerentcohssaveryshortpethl'orthegesrromthevalve j meant I and limtbovmbemd toan mt mp mt mm secured to the end subjected to heat changes.

Wt 9 w The other end of the tube is and while the eon- Other objectswill be made'clear in connection 235?; the gig with h descrip ion f oneem dim n t The upper thermostat is h'asltsbese a secured inventlonfll stutedintheaccomr ri ed w intliewau tthetenkendaohann luextende lugs.-g66dcwnnrdlyirombueltonthcoutsideo! Thecasting'lhasasmallelllendinz thetank to hold the casting 1 at a substantially fixed distance from thethermostat, A bell crank lever 25 is horiziontally pivoted at the upperend of channel 24 and has its vertical face engaged by the end of therod 22 of the thermostat I9 while its horizontal face rests upon theupper end of a vertical push rod 26 extending downwardly inside thechannel.

. The push rod 26 is made in two sections joined by a coupling 21threaded to the two ends in opposite directions to provide for adjustingthe over-all length of the rod. The lower end of therod 26 passesthrough the top of casting I and engages a triangularly shaped ledge 28which is pivoted to a short stub vertical push rod 2!.

Normally the ledge 28 is held against pivoting on the rod 29 so thatwhen rod 28 presses downwardly upon the ledge it moves the rod 28 downwardly. The rod 2! rests upon the center of a disk 30 which in turncontacts the rim of a con-.

I disk again seats. Spring tends to support the weight of disk 9 andhold it against the seat.

In operation, when the water in tank I cools, the tube 2| of thermostatI! contracts and causes its rod 22 to move outwardly against the bellcrank lever 25. This forces push rod 26 downwardly against ledge 28,thereby pressing rod 29 downwardly against disk 30 which in turn snapsspring 2| past center, opening valve 9 and releasing the gas to theburner. Likewise, when the water in tank I becomes heated, tube 2| ofthermostat l9 expands'and withdraws rod 22 inwardly allowing the bellcrank lever 25 to pivot away i from rod 28. Spring 3| then snaps overcenter 26. and effects and lifts rod 29, ledge'28 and rod seating of thevalve disk 9.

In order to provide the safety feature of preventing the valve I frombeing actuated to open position by thermostat it in case the pilot flamebecomes extinguished, the ledge 22 has its vertical face engage one endof a lever 22 which is pressed against-it by a spring 24 to hold theledge in normal position. The other end of.lever 23 is engaged by thecontrol rod 22 of thermostat 2|.

. When the thermostat is cold, as when the pilot is extinguished itstube 2| contracts and the consequent outward movement of rod 22 operateslever 32 against spring ll and away from the ledge 2| having acylindrical tank disposed with its axis I vertical, a heating burnerbeneath said tank, a layer of heat insulation around the tank, acylindrical casing enclosing the insulation and tank and substantiallyconcentric with the tank to' so as to give the latter no support.Thereafter,

when thermostat ll calls for heat and rod 2! lowers, the ledge 28 merelydrops away from the rod and does not eflect a push-on rod 22.

Upon lighting of the pilot burner again thermostat 2| will become heatedand allow spring 34 to press lever 23 back to normal position holdingledge 22 in a non-pivotal relation.

The entire control mechanism takes up little space and can be placedwholly inside the casing 'ofthetank. Itisreadilyadiustedbymeanso! thecoupling 21 on rod 26 andlis simple'to main- .tain. n. desired themanually controlledpilot valve it may be additions-l1! shut oil bytherprovide for a uniform thickness of insulation with a minimum ofspace between the casing and tank. gas control devices disposed entirelyinside said casing and comprising a casting providing a main valvechamber having a connection for the gas supply pipe and a connection forthe burner with a snap action valve disposed therebetween, a pilotburner secured to said casting and extending to casing.

2. In combination in a domestic water heater having a cylindrical tankdisposed with its axis vertical, a heating burner beneath said tank, alayer of heat insulation around the tank, a cylindrical casing enclosingthe insulation and tank and substantially concentric with the tank toprovide for a uniform thickness'of insulation with v a minimum of spacebetween the casing and tank,

gas control. devices disposed entirely inside said casing and comprisinga c valve chamber having a connection for-the gas supply pipe and aconnection for the burner with a snap action valve disposedtherebetween, a pilot burner secured to said casting and extending to apoint relative to the main burner to efl'ect lighting of the latter, athermostat responsive to the temperature of the water inside the tank tooperate said valve, said thermostat being disposed above said valve andextending horizontally through the wall of the tank and being connectedwith said valve by a vertically reciprocating push'rod disposed withinthe space provided for insulation between the tank and outer cylindricalcasingfand a thermostat responsive to a temperature produced by thepilot flame, and meanstodisconnectsaidpushrodtopreventthe opening oi'the valve by it when said second thermostat moves to a positionresponsive to failure of the pilot.

3. In a gas burner control, a thermostat, a rod disposed to be movedlongitudinally by the thermostat against a bell crank lever pivoted to aconditions.

mar R. KOPPIL.

ing providing a main

